With initial reference to FIG. 1, a vehicle 100 having a conventional lane keeping system is shown traveling in a direction 104 along a road 108. The road 108 includes a plurality of lane lines 112a, 112b, and 112c (collectively “lane lines 112”). The lane lines 112 are solid or dashed lines depending on a configuration of the road 108. Lane lines 112a and 112b define lane 116a in which the vehicle 100 is traveling. Similarly, lane lines 112b and 112c define another lane 116b. The lane keeping system of the vehicle 100 captures image data corresponding to an image area 120 in front of the vehicle 100. Using this image data, the lane keeping system operates a steering assist system of the vehicle 100 to keep the vehicle 100 traveling along a desired path 124, e.g., a center of the lane 116a. 
Conventional lane keeping systems, however, are ineffective in certain scenarios. In FIGS. 2A and 2B, the road 108 is a highway or an expressway. FIG. 2A illustrates an entrance/on-ramp lane 200 to the road 108. The entrance/on-ramp lane 200 is defined by inner and outer lane lines 204a and 204b, respectively. In this scenario, the lane keeping system incorrectly detects the outer lane line 204b of the entrance/on-ramp lane 200 in image area 208 as one of two lane lines to be used for lane keeping. The lane keeping system then operates the steering assist system to keep the vehicle 100 traveling along a path 212 that does not correspond to the center of the lane 116a and thus could cause the vehicle 100 to veer out of the lane 116a and/or off the road 108.
Similarly, FIG. 2B illustrates an exit/off-ramp lane 220 from the road 108. The exit/off-ramp lane 220 is defined by inner and outer lane lines 224a and 224b, respectively. In this scenario, the lane keeping system incorrectly detects the outer lane line 224b of the exit/off-ramp lane 220 in image area 228 as one of two lane lines to be used for lane keeping. The lane keeping system then operates the steering assist system to keep the vehicle 100 traveling along a path 232 that does not correspond to the center of the lane 116a and thus could cause the vehicle 100 to veer out of the lane 116a and/or off the road 108.
FIGS. 2C and 2D illustrate turn lane and intersection scenarios, respectively. In FIG. 2C, a turn lane 240 is defined by lane lines 244a and 244b, along with initial lane line 112a. In this scenario, the lane keeping system incorrectly detects lane line 244b of the turn lane 240 in image area 248 as one of the two lane lines to be used for lane keeping. The lane keeping system then operates the steering assist system to keep the vehicle 100 traveling along a path 252 that does not correspond to the center of the lane 116a and thus could cause the vehicle 100 to veer out of the lane 116a and/or off the road 108.
In FIG. 2D, on the other hand, an intersecting lane 260 is defined by inner and outer lane lines 264a and 264b, respectively. In this scenario, the lane keeping system incorrectly detects lane line 264b of the intersecting lane 260 in image area 268 as one of the two lanes to be used for lane keeping. The lane keeping system then operates the steering assist system to keep the vehicle 100 traveling along a path 272 that does not correspond to the center of the lane 116a and thus could cause the vehicle 100 to veer out of the lane 116a and/or off the road 108.
Thus, while such lane keeping systems work for their intended purpose, there remains a need for improvement in the relevant art.